AUTHOR=Barrios Evan L. , Leary Jack R. , Darden Dijoia B. , Rincon Jaimar C. , Willis Micah , Polcz Valerie E. , Gillies Gwendolyn S. , Munley Jennifer A. , Dirain Marvin L. , Ungaro Ricardo , Nacionales Dina C. , Gauthier Marie-Pierre L. , Larson Shawn D. , Morel Laurence , Loftus Tyler J. , Mohr Alicia M. , Maile Robert , Kladde Michael P. , Mathews Clayton E. , Brusko Maigan A. , Brusko Todd M. , Moldawer Lyle L. , Bacher Rhonda , Efron Philip A. TITLE=The post-septic peripheral myeloid compartment reveals unexpected diversity in myeloid-derived suppressor cells JOURNAL=Frontiers in Immunology VOLUME=15 YEAR=2024 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1355405 DOI=10.3389/fimmu.2024.1355405 ISSN=1664-3224 ABSTRACT=Introduction

Sepsis engenders distinct host immunologic changes that include the expansion of myeloid-derived suppressor cells (MDSCs). These cells play a physiologic role in tempering acute inflammatory responses but can persist in patients who develop chronic critical illness.

Methods

Cellular Indexing of Transcriptomes and Epitopes by Sequencing and transcriptomic analysis are used to describe MDSC subpopulations based on differential gene expression, RNA velocities, and biologic process clustering.

Results

We identify a unique lineage and differentiation pathway for MDSCs after sepsis and describe a novel MDSC subpopulation. Additionally, we report that the heterogeneous response of the myeloid compartment of blood to sepsis is dependent on clinical outcome.

Discussion

The origins and lineage of these MDSC subpopulations were previously assumed to be discrete and unidirectional; however, these cells exhibit a dynamic phenotype with considerable plasticity.